OSU researchers warn climate change will impact Eugene's drinking water

Study: Higher temperatures will result in lower snowpack in McKenzie watershed

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EUGENE, Ore. — The average temperature on Earth could increase by 3.6 degrees by the middle of this century, according to data from climate change researchers in nearly 20 countries. And that increase is enough to potentially affect the main source of Eugene-Springfield's drinking water, according to a study by Oregon State University scientists.

The McKenzie River is the major source of drinking water in the Eugene-Springfeld area. The single-digit increase in temperatures predicted worldwide means the snowpacks that feed the river could drop by 56 percent between 2040 and 2060, according to the OSU study.

The study simulated snowpacks of the McKenzie watershed using 20 years of data, factoring in the 3.6-degree average temperature increase. It concluded that areas such as the Willamette Valley, that rely on low elevation snowpacks for much of their water, face special risks that need to be planned for.

In low elevation mountain ranges, snow often falls near the freezing point so it takes only a small rise in temperature for snow to change to rain. "As more precipitation falls as rain, there will be more chance of winter flooding as well as summer drought in the same season," the OSU study said.

And Oregonians need to be thinking and planning for these future changes, said Eric Sproles, a researcher for the Oak Ridge Institute for Science and Education, which is part of the U.S. Department of Energy Institute.

"The timing and delivery of water is projected to change in the future. What that means is because the supply side is changing, we need to rethink the demand side and re-evaluate our use," said Sproles, who led the study as a doctoral student at OSU. "Some of the decisions are going to be ones we don't want to make."

"We have irrigation, we have municipal use, we have endangered species, hydropower and recreation that we're all using this water for," he said. "This isn't a doomsday tale, it's more of a cautionary advice note."

Sproles said the watershed's future could have implications on the entire Willamette Valley, home to more than 70 percent of Oregon's population, not just the McKenzie River basin. This is because almost 25 percent of the Willamette River's flow comes from the McKenzie, he said.

Officials at the Eugene Water and Electric Board said they're not too worried about the OSU report's findings, and that they plan to continue to seek new ways to promote responsible and sustainable use of water from the McKenzie watershed.

EWEB recently sponsored its own study, which found the geomorphology of the McKenzie River basin provides for a much slower water flow system that is less affected by climate change and snowpack melt due to the spongelike qualities of the volcanic rocks in the upper cascades, according to Jill Hoyenga, EWEB water resource and system planner.

"Snow and rain soak into that spongy rock formation," she said. "The snowpack is important but the rain will also soak into the ground water. We don't anticipate that climate change will have a huge effect on our water supply in the next few decades."

One group that is worried about the impact of a melting snowpack is the McKenzie Watershed Council.

"The staff here would be concerned about any models that predict water temperature to rise or snow levels to change over time and we would expect those changes to threaten an endangered species here in the McKenzie watershed such as spring chinook or bull trout," said Projects Manager Jared Weybright.

Although the council is proactive in its attempts to rectify the problem, Weybright said, the issue of climate change is something that needs to be taken on at a national and international level to prevent future temperature increases and the loss of more snowpack.

John DeVoe, executive director of lobbyist group WaterWatch Oregon, said the fight will need to continue on the local level through utility boards and environmental groups as well as having sweeping policy changes at the legislative level.

"I've heard it described as a train wreck in slow motion," DeVoe said of climate change policy.